1. Field of the Invention
The present invention relates generally to screwdrivers and, more particularly, to a screwdriver which provides selective transmission of rotational movement of a tool handle to the driving shaft.
2. Discussion of the Prior Art
A common problem experienced with conventional screwdrivers arises due to the need for repositioning the tool on the screw after each turn of the screwdriver in order to continue threading or unthreading the screw, as desired.
This problem makes it difficult to use the conventional device either when the screw head is not clearly visible, or when the user is in an awkward or off balanced position.
One solution to this problem is to provide a ratcheting screwdriver which allows the handle of the screwdriver to free wheel in one prescribed rotational direction relative to the shaft of the tool so that a constant axial force may be applied to the tool while the handle is rotated repeatedly back and forth, and rotation of the handle is only transmitted to the shaft when the handle turns in a direction opposite the prescribed direction.
Although such tools represent an improvement over conventional screwdrivers, they are expensive and complex, requiring numerous interfitting parts. Because of this added complexity, these tools are uneconomical to produce.